fifo_segment.h revision ef4f3e7f
1/*
2 * Copyright (c) 2016-2019 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
6 *
7 *     http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15#ifndef __included_fifo_segment_h__
16#define __included_fifo_segment_h__
17
18#include <svm/ssvm.h>
19#include <svm/svm_fifo.h>
20
21typedef enum
22{
23  FIFO_SEGMENT_FTYPE_NONE = -1,
24  FIFO_SEGMENT_RX_FIFO = 0,
25  FIFO_SEGMENT_TX_FIFO,
26  FIFO_SEGMENT_N_FTYPES
27} fifo_segment_ftype_t;
28
29#define FIFO_SEGMENT_MIN_LOG2_FIFO_SIZE 12	/**< 4kB min fifo size */
30#define FIFO_SEGMENT_MIN_FIFO_SIZE 4096		/**< 4kB min fifo size */
31#define FIFO_SEGMENT_MAX_FIFO_SIZE (2 << 30)	/**< 2GB max fifo size */
32#define FIFO_SEGMENT_ALLOC_BATCH_SIZE 32	/* Allocation quantum */
33
34typedef enum fifo_segment_flags_
35{
36  FIFO_SEGMENT_F_IS_PREALLOCATED = 1 << 0,
37  FIFO_SEGMENT_F_WILL_DELETE = 1 << 1,
38} fifo_segment_flags_t;
39
40typedef struct fifo_segment_slice_
41{
42  svm_fifo_t *fifos;			/**< Linked list of active RX fifos */
43  svm_fifo_t *free_fifos;		/**< Freelists by fifo size  */
44  svm_fifo_chunk_t **free_chunks;	/**< Freelists by chunk size */
45  uword n_fl_chunk_bytes;		/**< Chunk bytes on freelist */
46} fifo_segment_slice_t;
47
48typedef struct
49{
50  fifo_segment_slice_t *slices;		/** Fixed array of slices */
51  ssvm_shared_header_t *ssvm_sh;	/**< Pointer to fs ssvm shared hdr */
52  uword n_free_bytes;			/**< Segment free bytes */
53  u32 n_active_fifos;			/**< Number of active fifos */
54  u32 max_log2_chunk_size;		/**< Max log2(chunk size) for fs */
55  u8 flags;				/**< Segment flags */
56  u8 n_slices;				/**< Number of slices */
57} fifo_segment_header_t;
58
59typedef struct
60{
61  ssvm_private_t ssvm;		/**< ssvm segment data */
62  fifo_segment_header_t *h;	/**< fifo segment data */
63  u8 n_slices;			/**< number of fifo segment slices */
64} fifo_segment_t;
65
66typedef struct
67{
68  fifo_segment_t *segments;	/**< pool of fifo segments */
69  uword next_baseva;		/**< Where to put the next one */
70  u32 timeout_in_seconds;	/**< Time to wait during attach */
71} fifo_segment_main_t;
72
73typedef struct
74{
75  ssvm_segment_type_t segment_type;	/**< type of segment requested */
76  u32 segment_size;			/**< size of the segment */
77  int memfd_fd;				/**< fd for memfd segments */
78  char *segment_name;			/**< segment name */
79  u32 *new_segment_indices;		/**< return vec of new seg indices */
80} fifo_segment_create_args_t;
81
82#define fifo_segment_flags(_fs) _fs->h->flags
83
84int fifo_segment_init (fifo_segment_t * fs);
85int fifo_segment_create (fifo_segment_main_t * sm,
86			 fifo_segment_create_args_t * a);
87int fifo_segment_attach (fifo_segment_main_t * sm,
88			 fifo_segment_create_args_t * a);
89void fifo_segment_delete (fifo_segment_main_t * sm, fifo_segment_t * fs);
90fifo_segment_t *fifo_segment_get_segment (fifo_segment_main_t * sm,
91					  u32 fs_index);
92u32 fifo_segment_index (fifo_segment_main_t * sm, fifo_segment_t * fs);
93void fifo_segment_info (fifo_segment_t * seg, char **address, size_t * size);
94
95/**
96 * Allocate fifo in fifo segment
97 *
98 * @param fs		fifo segment for fifo
99 * @param data_bytes	size of default fifo chunk in bytes
100 * @param ftype		fifo type @ref fifo_segment_ftype_t
101 * @return		new fifo or 0 if alloc failed
102 */
103svm_fifo_t *fifo_segment_alloc_fifo_w_slice (fifo_segment_t * fs,
104					     u32 slice_index,
105					     u32 data_bytes,
106					     fifo_segment_ftype_t ftype);
107
108/**
109 * Free fifo allocated in fifo segment
110 *
111 * @param fs		fifo segment for fifo
112 * @param f		fifo to be freed
113 */
114void fifo_segment_free_fifo (fifo_segment_t * fs, svm_fifo_t * f);
115
116/**
117 * Try to preallocate fifo headers
118 *
119 * Tries to preallocate fifo headers and adds them to freelist.
120 *
121 * @param fs		fifo segment
122 * @param batch_size	number of chunks to be allocated
123 * @return		0 on success, negative number otherwise
124 */
125int fifo_segment_prealloc_fifo_hdrs (fifo_segment_t * fs, u32 slice_index,
126				     u32 batch_size);
127
128/**
129 * Try to preallocate fifo chunks on segment
130 *
131 * Tries to preallocate chunks of requested size on segment and adds them
132 * to chunk freelist.
133 *
134 * @param fs		fifo segment
135 * @param chunk_size	size of chunks to be allocated in bytes
136 * @param batch_size	number of chunks to be allocated
137 * @return		0 on success, negative number otherwise
138 */
139int fifo_segment_prealloc_fifo_chunks (fifo_segment_t * fs, u32 slice_index,
140				       u32 chunk_size, u32 batch_size);
141/**
142 * Pre-allocates fifo pairs in fifo segment
143 *
144 * The number of fifos pre-allocated is the minimum of the requested number
145 * of pairs and the maximum number that fit within the segment. If the maximum
146 * is hit, the number of fifo pairs requested is updated by subtracting the
147 * number of fifos that have been successfully allocated.
148 *
149 * @param fs		fifo segment for fifo
150 * @param rx_fifo_size	data size of rx fifos
151 * @param tx_fifo_size	data size of tx fifos
152 * @param n_fifo_pairs	number of pairs requested. Prior to returning, this
153 * 			is decremented by the the number of pairs allocated.
154 */
155void fifo_segment_preallocate_fifo_pairs (fifo_segment_t * fs,
156					  u32 rx_fifo_size,
157					  u32 tx_fifo_size,
158					  u32 * n_fifo_pairs);
159/**
160 * Grow fifo size by adding an additional chunk of memory
161 *
162 * @param fs		fifo segment for fifo
163 * @param f		fifo to be grown
164 * @param chunk_size	number of bytes to be added to fifo
165 * @return		0 on success or a negative number otherwise
166 */
167int fifo_segment_grow_fifo (fifo_segment_t * fs, svm_fifo_t * f,
168			    u32 chunk_size);
169
170/**
171 * Collect unused chunks for fifo
172 *
173 * @param fs		fifo segment for fifo
174 * @param f		fifo whose chunks are to be collected
175 * @return		0 on success, error otherwise
176 */
177int fifo_segment_collect_fifo_chunks (fifo_segment_t * fs, svm_fifo_t * f);
178
179/**
180 * Fifo segment estimate of number of free bytes
181 *
182 * Returns fifo segment's internal estimate of the number of free bytes.
183 * To force a synchronization between the segment and the underlying
184 * memory allocator, call @ref fifo_segment_update_free_bytes
185 *
186 * @param fs		fifo segment
187 * @return		free bytes estimate
188 */
189uword fifo_segment_free_bytes (fifo_segment_t * fs);
190
191/**
192 * Update fifo segment free bytes estimate
193 *
194 * Forces fifo segment free bytes estimate synchronization with underlying
195 * memory allocator.
196 *
197 * @param fs		fifo segment
198 */
199void fifo_segment_update_free_bytes (fifo_segment_t * fs);
200
201/**
202 * Number of bytes on chunk free lists
203 *
204 * @param fs		fifo segment
205 * @return		free bytes on chunk free lists
206 */
207uword fifo_segment_fl_chunk_bytes (fifo_segment_t * fs);
208u8 fifo_segment_has_fifos (fifo_segment_t * fs);
209svm_fifo_t *fifo_segment_get_slice_fifo_list (fifo_segment_t * fs,
210					      u32 slice_index);
211u32 fifo_segment_num_fifos (fifo_segment_t * fs);
212u32 fifo_segment_num_free_fifos (fifo_segment_t * fs);
213/**
214 * Find number of free chunks of given size
215 *
216 * @param fs	fifo segment
217 * @param size	chunk size of interest or ~0 if all should be counted
218 * @return	number of chunks of given size
219 */
220u32 fifo_segment_num_free_chunks (fifo_segment_t * fs, u32 size);
221
222void fifo_segment_main_init (fifo_segment_main_t * sm, u64 baseva,
223			     u32 timeout_in_seconds);
224
225format_function_t format_fifo_segment;
226format_function_t format_fifo_segment_type;
227
228#endif /* __included_fifo_segment_h__ */
229
230/*
231 * fd.io coding-style-patch-verification: ON
232 *
233 * Local Variables:
234 * eval: (c-set-style "gnu")
235 * End:
236 */
237